The invention relates to a lightweight vertically perforated brick having a perforation pattern which exhibits a plurality of perforation rows, extending in the longitudinal direction, and webs separating the perforations from one another. Bricks of this type are used, predominantly in housing construction, for carrying out brick masonry work. They are laid in a conventional manner or are laid as flat bricks with thin-bed mortar.
The known bricks of this type have slot perforations, the perforations having a rectangular, elliptical, or in any case elongate cross-section and forming continuous vertical channels which are open at the top and bottom. The longitudinal axis of the perforation cross-section extends in the longitudinal direction of .the bricks and the perforations of neighboring perforation rows are frequently offset in the longitudinal direction with respect to one another. Known bricks which are best in terms of heat insulation, have a coefficient of thermal conductivity of .lambda.=0.16 [W/m.K] or worse.
Endeavors to make the slot-shaped perforations longer are limited by an increased brittleness of the brick, because such long-web bricks are resistant neither to compression nor to transverse tension. The resistance to compression and the resistance to transverse tension constitute hitherto insurmountable barriers on the road to providing bricks with an even better heat-insulating capacity. Finally, it should be stressed that the acoustic phenomenon of the so-called flank transmission occurs in the case of known bricks, optimized in terms of heat insulation, with slot perforations.